Apparatus for guiding threads



Sept. 20, 1932. BAMGAN 1,878,455

APPARATUS FOR GUIDING THREADS Filed May 51, 1929 ATTORNEY Patented Sept. 20, 1932 UNITED STATES PATENT lot-"Flor.

THOMAS F. 'Z BANIGAN, OF BUFFALO, NEW ,YORK, ASSIGNOR '10 D'D' .PONT RAYON" COH- PANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE APPARATUS FOR GUIDING THREADS Application filed May 31,

This invention relates to the art of manufacturing artificial silk and more particularly to a process and means for, guiding freshly coagulated threads in the coagulating bath with or without stretching said threads.

In the production of artificial silk from viscose it has been the practice to spin a solution of the latter in a coagulating bath. The

freshly coagulated threads were guided through the bath by various thread guides arranged in divers set-ups. Stretching of freshly coagulated threads not only gave the.

threads a finer filament denier but also imparted thereto increased tensile strength. The thread guides above-mentioned were, therefore, used to impose a tension on the threads whereby the latter werestretched. In practice it has been found that these'thread guides, though they imposed a tension on the threads, did so in a most irregular manner. Very often, threads produced in the same set-up possessed different characteristics, whereby it was impossible to produce a fabric of uniform quality.

I have found that I can vercome the above-mentioned defects by using roller guides to direct the freshly coagulated threads. instead of the fixed-thread guides used prior to this invention. These roller guides may,

if desired, not only function to direct or change the direction of the freshly coagulated threads but also impose a uniform'tension and/or buildit up to, the desired degree. It is therefore an object of this invention to provide an apparatus and method of guiding freshly coagulated threads through the coagulating bath including roller guides.

Another object of this invention is to provide an apparatus and method for producing a substantially uniform tension and/or build it up to the desired degree on freshly coagu lated threads.

A further object of this invention is to provide a method and apparatus for directing the travel of freshly coagulated threads through the coagulating bath with or without stretching the same, comprising a roller guide mounted on a vertical axle.

A specific object of this invention is to pro.-

1929. Serial No; 367,443.

Figure 1 illustrates the plan view of one modification of a set-up including the roller guide constituting this invention.

Figure 2 is a side elevation of the apparatus illustrated in Figure 1.

Figure 3 illustrates a plan view ofa set-up utilizing a plurality of roller guides constituting this invention whereby a-long bath travel and gradually built-up tension are obtained.

Figure 4 is a side elevation of the set-up illustrated in Figure 3.

Figure 5 illustrates a plan view of a set-up including a guide serving as a bundling device and a roller guide.

Figure 6 is a plan viewof the set-up illustrated in Figure 5.

Figure 7 illustrates one manner of mounting the roller guide in the bath.

Referring now to the drawing wherein like reference numerals designate like parts, the reference numeral 1 designates a roller constitutin a guide freely mounted on a vertical ax e 2 of any suitable material disposed in a receptacle 3 containing the coagulating bath in any suitable manneri In the drawing and more particularly in Figure 5, the vertical axle 2 is rigidly mounted in any suitable support or fittin 4 made of or surfaced with lead or any ot er material which is not attacked by the coagulating .bath liquor. The roller 1, as above stated, is freely mounted on-the vertical axle. This is ob tained by making the center hole 5 thereof slightly larger in diameter than the diam eter of the vertical axle, thus permitting the roller 1 to ride freely on the axle. For conably rubber, is provided. This stop is positioned below the normal operating position of the rollerand at such a point that it will permit the roller 1 to follow the surface of the coagulating bath liquor during operation. If desired, removable retaining means 7 may be provided on the upper end of the axle whereby accidental displacement of the guide therefrom is prevented. In my preferred embodiment, I do not use any retaining means 7, but make the axle 52 extend a small distanceabove the normal level of the coagulating liquor.

The roller may be made of any size depending on its purpose and the tension which it is desired to develop. It may be a roller with a smooth flat periphery, but I prefer a roller provided with a peripheral groove 8 of any desirable dimension through which the threads pass. This roller maybe solid, hollow or even of a discontinuous surface. It may be made to develop more or less tension depending on the amount of liquid set in motion by its rotation in the bath. This can, of course, be regulated by the size of the roller or by the addition of various means such as depressions or projections on the sides or on the'periphery of the roller.

It is desirable that this roller be one which floats on the surface of the bath during operation and/or follows the variations in the level of said bath. To attain this, the density of the roller need not be less than that of the bath. It may, in fact, be greater than that of the bath so that normally it will sink. In this case, its density as compared to the bath should be relatively low so that when the device is in operation it will ride at or just below the surface ofthe bath. The roller, of course, may actually be formed of such material or composition that it will float. To this end,'I have found that hollow rollers made from glass, pyroxylin, bakelite, and the like, produce satisfactory results. I prefer, however, to use a solid roller formed of bakelite, yroxylin, hard rubber or any other suitable material.

These rollers guides are disposed in the bath, as above described, atany point in relation to the spinnerets and other parts of the spinning machine. It is to be understood that such conditions as the viscose compositions and characteristics, coagulating bath composition, rate or flow, temperature, speed of spinning, denier of the threads, etc., all have a controlling effect on the position of the guide, whether it be a fixed guide or a roller guide.

In operation, the roller 1 is disposed on the vertical axle 2. In threading the machine, theethreads after issuing from the spinneret 9 are passed along the surface of the bath in the groove 8 and around the roller, which is in view, through the fixed guide 10, if used, and thence to the bobbin 11 or over a godet wheel and into a bucket or other collecting a density greater than that of the bath is used, it is momentarily lifted to the bath surface where it will be maintained by the thread travel. During spinning, the threads are always near the surface and the quality of spinning can be thoroughly studied without interrupting it. If a thread Wraps around the roller or axle, as frequently happens, the roller may be promptly lifted oif its axle and the position cleared of any obstructions and returned to operation with a minimum delay, the roller also may be removed very readily and easily for inspection or replacementsince there is no means preventing its removal.

The roller guide, above described, eliminates the necessity for thrust or retaining bearings of any sort whereby a very certain cause of uneven tension is eliminated. Due to the bath, the roller maintains a constant resistance since it follows the momentary changes in depth of the bath. Whenever roller guides are used, whether on-vertical or horizontal axles, it is essential for uniform performance that they be mounted on axles which are of uniform levelness. When a horizontal axle is used, this is very diflicult to obtain and check. In the case of the vertical axle it can easily be made perpendicular and its position checked and, whenever necessary, corrected with ease.

Fromthe above it is obvious that some tension, although small, is produced by the threads passing around the roller guide. This tension is caused by the resistance of the bath to the rotation of the roller and to the friction between the roller and its axle. There is, however, substantially no sliding friction of the threads on the roller. Since the tension produced is small, these roller guides may be used to give a long straight travel to the threads, or by having the threads turn back around the roller they may be used to give a long travel in a restricted space. The length of travel may be made of any desired amount by employing a plurality of said guides arranged in series as illustrated in Figures 3 and 4. It can also be used as adevice for not only changing direction but also as a means for preventing the whipping and swaying of the long lengths of threads. When these floating rollers are used in series, it is possible to gradually build up the tension, producing threads of very high tensile strength, without sacrificing the high elongation Which is valuable and which is usually reduced in the prior methods. To attain this result, there is provided a series of rollers, each succeeding one cooperating with the one immediately prior thereto to effect a gradual stretching of the threads. In such arrange ments, the threads after coagulation may be guided through or floated on the surface of the bath until they acquire suflicient strength to withstand the stretching operation. These floating rollers may also be used in combination with other thread guides, the guide 10 in the drawing being the usual hook guide. In such a set-up the roller guides may be used in the early stages of coagulation when the threads cannot withstand much tension, the fixed guides producing a tension. These guides may also be used in combination with tension devices disposed inside or outside of the bath such as positively driven rollers rotating at different speeds.

If desired, a guide 12 may be used in conjunction with the roller guides 1. This guide 12 is disposed in the bath prior to the roller guide 1 and is formed with a groove 13, preferably V-shaped, through which the freshly coagulated threads pass (see Figures 5 and 6). In addition to serving as means fordirecting the freshly-coagulated threads through and to the roller guide 1, the guide 12 also functions as a bundling device. When this set-up is used, the freshly coagulated threads pass from the sp-inneret 9 to the guide 12, whereby the threads are bundled, and thence to the roller guide 1 from which they pass through the fixed guide 10 to the bobbin 11 or to a bucket or other receptacle in the usual manner. Any number of these bundling devices may be used. Satisfactory results. have been obtained when one such guide has been used. Itis to be understood that the guide 12 is not limited to the precise arrangement illustrated in Figures 5 and a 6, but may be used in combination with any of the various other set-ups.

From the foregoing description it is apparent that this invention contemplates the use of floating roller guides, i. e., roller guides mounted for free movement at or near the surface of the bath. It is not restricted to the specific modification above-described wherein vertical axles are used but also includes axles extending upwardly in the bath and/or disposed at various angles to the vertical. Guide rollers mounted on axles inclined from the vertical may be used alone or in combination with guide rollers mounted on vertical axles and/or fixed guides. When rollers mounted on inclined axles are used in combie natlon with rollers mounted on vertical axles,

it is essential that all similar positions on a spinning machine be substantially the same, otherwise consistent results will not be obtained throughout the operation of the machine. The axles may be inclined from the vertical at various angles. I have found that inclinations not more than 60 have given satisfactory results.

The roller guides constituting this invention have a very useful application in highspeed spinning. It is known that as the speed of spinning increases, the tension developed by a guide also increases and the travel of the threads must increase to properly coagulate them. The use of roller guides permits the required bath travel in a minimum space and does not increase the tension to the degree that other guides do.

This invention, though it has been described with particular reference to the spinning of viscose solutions, is not limited thereto. It may be used in any wet spinning process'and even in dry spinning processes.

I claim:

1. In an apparatus, including a bath, for producing artificial silk, a thread guide comprising a roller floating in said bath and having its periphery lying in a horizontal plane.

2. In an apparatus, including a bath, for producing artificial silk, a thread guide comprising an upwardly extending axle disposed in said bath and a roller free y mounted on said axle and adapted-to follow the variations in the level of said bath.

3. In an apparatus, including a bath, for producing artificial silk, a thread guide comprising an upwardly extending axle disposed in said bath and a roller freely mounted on said axle and adapted to follow the variations in the level of said bath, said roller having a groove in the periphery thereof.

4. In an apparatus, including a bath, for producing artificial silk, a thread guide comprising a vertical axle disposed in said batl:i

and a roller freely mounted on said axle an adapted to follow the variations in the level of said bath. U

5. In an apparatus, including a bath, for producing artificial silk, a thread guide comprising a vertical axle disposed in said bath, and a roller freely mounted on said axle and adapted to follow the variations in the level of said bath, said roller having a groove 1n the periphery thereof.

6. In an apparatus, including a bath, for producing artificial silk, a thread gurde comprising a vertical axle disposed n sald bath, a roller freely mounted on said axle and adapted to follow the variations 1n the level of said bath, and means to limit the downward movement of said roller.

7. In an apparatus, including a bath, for producing artificial silk, a series of thread guides, each of a plurality of said guides comprising an upwardly extending axle disposed in said bath and a roller freely mounted thereon and adapted to follow the variations producing artificial silk, 9. thread guide comprisin an upwardly extending axle disposed 1n sai bath and a roller freely mounted and capable of upward and downward movement on said axle, said roller having its periphery 5 lying in a horizontal plane.

In testimony whereof, I have afixed any signature to this specification.

THOMAS F. BANIGAN. 

